Mammalian cells are capable of delivering multiple types of membrane capsules, also referred to as microvesicles, extracellularly. Such microvesicles shed by one cell can be taken up by another cell, thus allowing for intercellular communication and transport of molecules contained within the microvesicles. For example, the limiting membrane of late endosomes can fuse with the plasma membrane, leading to the extracellular release of multivesicular bodies (MVBs), initially contained within the endosomes, as exosomes. Also, budding viruses exploit the tumor susceptibility gene 101 (TSG101) protein and the highly conserved ESCRT (Endosomal Sorting Complex Required for Transport) machinery used for MVB formation to mediate the egress of viral particles from host cells.